1. Field of the Invention
The invention pertains generally to laminated glass structures, and more particularly to a shatter-resistant glass laminate for use in architectural applications.
2. Description of the Background Art
A variety of shatter-proof glass laminates and assemblies are known and used, particularly in the automotive industry. These glass constructions typically comprise two layers of plate glass bonded together by an interlayer of adhesive such as polyvinyl butyral resin. For example, U.S. Pat. No. 4,943,484 discloses a solar control glass assembly and method of making the same wherein two glass layers are bonded together by a polyvinyl butyral layer, and an induced transmission filter is bonded to one of the glass layers. U.S. Pat. No. 4,072,779 discloses a birefringent polyester film which may be bonded to a glass sheet by a layer of polyvinyl butyral adhesive. The cost involved in manufacture of such glass laminate structures, however, generally precludes their use in residential and commercial structure applications.
Glass laminate structures for architectural use are also known. For example, U.S. Pat. No. 4,943,484 discloses a security film for shatter proofing windows, wherein a plurality of polyester strata are bonded together as a film which is applied to window glass. U.S. Pat. No. 4,952,459 discloses a glass sheet and laminate at one side thereof which includes a flexible web of two polyester films bonded together which is adhered to a glass sheet on one or both sides. These lamination arrangements are generally expensive to manufacture, do not provide for enhanced protection against ultraviolet radiation, and do not necessarily meet the national standard for safety glazing materials for building use in the United States.
Accordingly, there is a need for a shatter resistant-glass for architectural applications which is simple and inexpensive to manufacture, which provides enhanced protection from ultraviolet radiation, and which meets the national test standard for shatter-resistant glass for use in building construction. The present invention satisfies these needs, as well as others, and generally overcomes the deficiencies found in the background art.
The foregoing patents reflect the state of the art of which the applicant is aware and are tendered with the view toward discharging applicant's acknowledged duty of candor in disclosing information which may be pertinent in the examination of this application. It is respectfully stipulated, however, that none of these patents teach or render obvious, singly or when considered in combination, applicant's claimed invention.